Conventional baby bottles with nipples are not easily filled with drinking fluids, such as water or juice. Further, conventional juice and water bottles are not adaptable for use with an infant's nipple. Thus, there have been attempts to design nipple adapters that can be fitted on a typical beverage bottle in place of the bottle cap. For example, U.S. Pat. No. 6,851,565 to Stephan discloses a nipple adapter including a collar having female threads for mating with the outer male bottle-top threads of a conventional narrow-diameter threaded-cap beverage container. However, as with the other known nipple adapter designs, the nipple adapter of the '565 Patent can only be used on standard beverage bottles having a specific thread pitch.
Accordingly, there is a need for a nipple adapter having a relatively simple construction that can be used on a variety of beverage bottles having differing thread pitches.